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What is a ZIP file?

Help your business save storage space and speed up email transmission time with ZIP files.

What is a ZIP file?

File compression is an incredibly important part of the digital workspace. We can send more data at faster speeds than has ever been possible, which is why ZIP files are such a popular tool for businesses all across the world. But a ZIP file?

ZIP files explained

ZIP is a widely used archive file format that’s used to compress one or more files together into a single location, reducing the overall size, and making it easier to transport the files. ZIP files work in much the same way as a standard folder on your computer. However, with zipped files, the content of the folder is compressed, reducing the amount of data used by your computer. So, if you want to know how to make a file smaller, it’s in your best interests to investigate the ZIP file format.

So, how can you identify a ZIP archive file? Simple. Whenever you see the extensions .ZIP or .zip at the end of a file, you’re looking at a ZIP file. The ZIP file format has been around for a long time, having been invented by Phil Katz back in 1986. Initially, Katz implemented ZIP files in his company’s PKZip program, but their usage eventually became widespread, and while there are many different file archive formats, ZIP is probably the most commonly used, primarily due to the popularity of the WinZip program in the 1990s.

How do ZIP files work?

ZIP files encode information into fewer bits – thereby reducing the size of the file or files – by removing redundant data. This is what’s referred to as 'lossless data compression', which ensures all of the original data is kept intact. Let’s look at a quick example to explain how this works.

Imagine a file that contains the following sentences:

  • The best sharing and storage solution for your business
  • Your business solution for the best sharing and storage

Each word in this file appears twice. Now, if each character and space in the file equals one unit of memory, then the entire file size would be 110 units. However, if you create a numbered code for the file, the data can be expressed in a different way:

  • 1 – The
  • 2 – best
  • 3 – sharing
  • 4 – and
  • 5 – storage
  • 6 – solution
  • 7 – for
  • 8 – your
  • 9 – business

Or to put it a different way, the sentence would now read: 123456789896712345. This means that the initial file size of 110 units can be reduced to just 18 units, which is a massive saving. The ZIP file format uses lossless compression algorithms to do exactly that, allowing you to express the same information in a more efficient way by simply removing the redundant data from the file.

When to use ZIP files at work

There are a broad range of potential uses for zipped files in a business setting. Being able to send large numbers of files over email is imperative. Say you need to send a big batch of files across to a colleague or client. Rather than laboriously uploading each file one by one as an email attachment, having to wait for each file to upload before attaching the next, you can simply zip all the documents at once and attach a single ZIP file to your email. You should also consider the potential storage solutions that the ZIP format provides. Rather than retaining all your business files in their original sizes, zipping the files can help to significantly reduce the amount of space that your old files take up.

What are the advantages and disadvantages of the ZIP file format?

Now that you know a little more about zipped files, it’s important to explore the potential advantages and disadvantages of using this type of archive file, particularly with regard to how to make a file smaller. First, and most obviously, ZIP provides users with the opportunity to save storage space and increase the efficiency of their computer. It’s also an effective way to improve email transfers, as you’ll be able to send emails much more quickly with smaller files. Furthermore, the ZIP file format will encrypt your private data, which is always important when you’re sending files over the Internet. In short, it’s a really simple way to maximise the efficiency of your file handling. Simply right-click on the files you want to zip, select 'Send to', click 'Compressed (zipped) folder', and you’re good to go.

However, there are a number of disadvantages associated with ZIP archive files that you should be aware of. Most importantly, some files cannot be compressed much more than they already are, including MP3 files and JPG files. So, if you work extensively with video and image files, the ZIP format might not help you save very much storage space. Then, you need to think about the security aspect of zipped files. Although zipped files are encrypted on completion, there’s no way for you to know what’s happening with your data when it’s initially uploaded to a file compression app, and no way to stop it falling into the wrong hands. Of course, you can use the built-in zipping functions that are available in Windows and Apple, but if you’re using an external compression app from a third-party provider, data security will always be a concern. It’s also worth remembering that ZIP file extensions can also get corrupted, and in some cases, corrupted data can affect the entire ZIP folder.

What is a 7z file?

When you’re researching ZIP files, you’ll probably come across the term '7z file' or '7-ZIP'. But what is a 7z file and how does it differ from the ZIP format? It’s very similar to other archiving formats like ZIP and RAR, but crucially, 7z files use a higher compression ratio. This means that there are fewer megabytes in each file, ensuring that users can make even greater storage savings. While 7z files may take a little longer to process, it’s likely to be the archive file of choice for anyone who’s focused on learning how to make file sizes smaller in the most effective way.

What are the alternatives to ZIP files?

Of course, the ZIP file format isn’t the only game in town when it comes to file compression. There are a broad range of archive file types, including RAR, TAR and 7z, as well as archiver and file compression software, such as WinRAR, ZIPx and PeaZip. But, as we’ve mentioned, there are a range of potential issues associated with ZIP files, including long wait times, duplicated files, file size limits and corruption.

Rather than wrestling with various file compressor apps, using cloud storage can provide a ZIP file alternative, removing the need for compression altogether. With Dropbox for example, there’s no long, multi-step process that you need to run through in order to store or send large files. Simply send a file or folder in its original size without compressing by clicking 'Share'. You can store and share files up to 50 GB, making it a fast, reliable way to share files without eating into your inbox or taking up disk space on your computer. Having said that, even if you need to work with compressed files, Dropbox can be an ideal platform, offering ZIP and RAR preview support, post-upload compression and support for editing.

Final word

In a nutshell, a ZIP file is a way to store or transfer data in a more efficient way. However, it’s not the only way to compress files, so be sure to look at the different compression options to work out the best archive file system for your needs.

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